Electrically operated piston gas-pump unit



Nov. 17, 1931. H. @LTE-N 1,832,588

ELECTRICALLY OPERATED PISTON vGAS PUMP-UNIT Wfl/V, Y,

Pam-17,1931.l HSILTEN 1,153.2,588

ELLECTRICALLY OPERATED PISTON GAS PUMP UNIT I' Tl MW M 'T Mw I miffl/627407".

New. i7, w31. H. Sim-EN ELECTRI-CALLY- OPERATED PISTON GAS PUMP UNITFiled Feb. ll, 1931 5 SheStS-Shet 5 Patented Nov. 17, 1931 HEINZ SILTEN,OF BERLIN,v GERMANY, ASSIGNOR4- TO VSAUERSTOFFCEN'JRAI-LJEI FURMEDIZINISCHE ZWECKE DR.

0F GERMANY.

Y v'Application filed February 11, 1931. Serial No. 515,121.

My invention relates tothe manufacture of electrically drivensmall-sized gas pumps of the piston type provided with centrifugallubrication. i y l v The invention consists inproviding a single castinghaving only one cover ,to act as vcasing for the pump and-the oilseparator, and covers also modifications wherein the motor is arrangedvin thecasingbeside the pump and the o ill separator. Itis immaterial vvheth'er 'special bushes, valvev seats, ,and the like are cast intothecylinder. or on to the journal 'or journals of the pump; and motor andfor the lvalve seats or notk One Aembodiment ofthe invention isillusrtrat'ed by `way of examplein'the accompanying drawings, in whichFigure 1 isa 'section along the pump a'Xis ofan electrically operatedsmall gas pump of the piston type with centrifugal lubrication,accordingvto the invention; Fig. 2, a section on theline .11,-B,

of Fig. 1; Fig. 3, a plan of Fig. 1' with Vthe cover removed; Fig.` 4, aview of the cover from the inside; Fig.` 5" a sectional view of thecover; Figi 6, a sectionof the casing for thepiston pump, the oilseparator and the motor g Fig. 7, a section on the line C-D, of Fig. 6,seen in the direction of the arrow; Fig.'8, a view of the casing forvthe piston pump and the oil separator; Fig. 9, a section on the lineBl-2F, of Fig. 8, seen in the direction of the arrow; and Fig.r10,`adiagram of the casing forthe piston pump and the oil separatorand of thecover." f

Like numeralsrefe'r to llike parts.

In the drawings, 1 is the casing,"2 the cover,`11 is the` eccentricshaft of the pump, 12 thefconnectiiig rod, 13 the piston pin,v 14 thepiston, 15 are piston rings forpacking the piston, -16 is theouterlbearing of the eccentric shaft-,l' the inner bearingy thereof, 18the driving wheel of the pump, 19 are fastening screws for the outerbearing, is a charging aperture for the' lubricating'oil ydisposed at asuitable' distance under the bearings of the pump shaft, 111 ascrew'plug for the charging aperture, 112adischaige screw for the oilseparator, 113 a vertical duct leading from the crank space up to thesurface of the casing land being in communication ERNST SILTEN OFvBERLIN, GERMANY,l A COMPANY .'ELEcz'r:RICALLYy OPERATED rrsr'onGAS-PUMP Unir with the atmosphere through the medium of the aperture11,41. Theduct 113 opens near the inner bearing 17, of the eccentricshaft 11. is the duct of the oil separator in the casing 1 and` leadsfrom thesurface of "x55 vthe casing 1 to the extension 116 of the oilseparator, the extension 116 being dimenlsioned so as to serve also' asair vessel. The discharge screw 112 serves for removing n from time totime therefuse collecting in "6"0 the extension ,116. 117 is a ductleading out of the extension 116. The rib 118 separates the duct 115fromthe duct 117.

Lubricating oi1`119 is kept inthe crank p ycase. `The lpiston 14;.lias anose 120 disposed 6'5 over the lubricating hole 121 of the connectingrod' 12. A bush 121 is inserted in the bore of; the cylinder to serve asbearing sleeve forthe piston.

' In the cover, the suction valve 21 and the "4h-fo pressure valve 22are arranged. Aperturas place thespace of the suction valve 21 intocommunication withV the outer air, and the space ofthe ypressure valve22 is connected by an opening with the pump space. w

Below the oil space of the pump the casing 1 contains' an opening forthema-gnetic iield 31 vand the armature 32 of the driving mot-or. Thedrivingdisc 33 is secured to the motorA shaft V810, and the belt 34passes over the discV 80 33 and the pulley 18 of the driving wheel ofthe pump. 35 and 36are the bearings'of the electric motor, 37 is theVvend shield bearing bracket, 38 are the brushes, and 39 is thecollector.` `The cover 2 isV provided on its in-f 85 side with a planesurface of the same type V'as that ofthe casing 1. The duct 115 of thecasing 1 extends into the recess 24 of the cover 2. A connecting channel23 leads from the chamber of the pressure valve 22 in an 90 obliquedirection down tothe recess 24.` An opening 25 leads in the cover 2 fromoutside to the recess 26 which isthe continuation of the outlet channel117. The opening 25 mayi be connected with an air piping 210, .as `95yshown in Fig. 10, and a suction piping, not

shown, may be connected to the cover 2 of the casing 1 so as to lead vtothe supply openof the suction valve 21.

Y' The threaded holes 122 in Fig. 3` servefor 100 securing the cover inposition, and the holes 27 in Fig. 4 hold the fastening screws of thecover 2. 28 in Figs. 4 and 5 is the seat for the springs of the suctionvalve 21. 29 is a seat ring cast into the cover 2 for the pressure valve22.

During the manufacture of the casting for the casing 1 the openings 110and 112 as well as the openings 123 for the fastening screws 19 of thebush 16 are recessed in addition to the openings stated. Subsequently,threads are cut into these openings. Furthermore, the holes 124 in Fig.10 are provided to secure the pump to its support.

The small piston gas pump is operated by connecting the electric drivingmotor with a source of current so that it rotates and, by means of thedriving disc 33, the belt 34 and the pulley 18, transmits its rotationto the eccentric shaft 11 of the pump, whereby the piston 14 is moved upand down. The connecting rod 12, at each rotation, dips once into theoil 119, picks up a dro of oil and throws it around inside the crancase. All parts of the crank case, including the insides of the bush 121and of the piston 14, are thus covered with oil which also reaches thenose 120 of the piston 14 whence it drops into the lubricating hole 121of the connecting rod 12 so that the piston pin 13 is oiled continually.At each rotation, owing to the descent of the piston 14, the space inthe crank case below the piston 14 is reduced in size, the excess airbeing pushed out into the open through the vert-ical duct 113 and theaperture 114. On the ascent of the piston 14 fresh air is drawn in inthe reversed manner, and, as the 4duct 113 opens near the inner bearing17, this fresh, and therefore cool, air strikes the inner bearing 1'7and cools it.

The pump further draws in air or another' gas through the suction valve21 and presses it out again from the cylinder space through the pressurevalve 22. lVhen gas is pressed out of the pressure valve 22 through theconnecting duct 23 into the recess 24, it will strike the wall of therecess 24. As all parts of the pump are heavily oiled, owing to theregular supply of the lubricant, drops of oil will often be found in thegas. These drops of oil then settle on the wall of the recess 24 and arethus separated Vfrom the gas. The purified gas then passes through theduct 115 and the outlet channel 117 to the opening 25 whence it isconducted away through the piping 210 for use, and the oil remains inthe separator wherein it drops down along the wall of the recess 24 andof the duct 115 to collect in the extension 116 which receives also allother liquid or solid matter separated from the gas when it strikes thewall of the recess 24. These substances can be removed from time to timeafter unscrewing the screw 112.

The pump may be used for pressing gas to any desired spot or removing ittherefrom, according to whether this spot be connected behind the piping210 or in front of the suction valve 21.

It is not necessary, though practical, to arrange the motor in the samecasing as the other parts of the plant. If the motor is self-contained,its frame is preferably of rectangular shape, as shown in Fig. 2, sothat the rest of the casing, as illustrated in Fig. 10, may be readilysecured to the motor frame by means of screws, However, instead of belowthe pump shaft, the motor may be secured beside the pump casing.

The casting for the small piston gas pump consists preferably ofsilumine, an alloy, the chief ingredients of which are silicon andaluminum. This substance possesses sufcient strength and density and isvery light in weight. 11s the electrically operated gas 3 pump is to berendered portable, light-ness is a very desirable feature. Silumine is,however, not suited to serve as substance from which bearings for steelshafts could be made. For this reason. a number of bronze bushes,l suchas the lbushes 121', 17 and 36, are provided in the casting 1 alreadyduring the casting process.

Parts of the valves 21 and 22 are cast into the casting 2 lfor otherreasons.

The castings 1 and 2 are constructed so as to require machining only ata few spots. ln the casting 1, only the upper and lower side, the innerwall of the bush 121', the bush 17, the surfaces hugged by the bush 16,and, in case the Vmotor is built into the casting 1, the surfaces towhich its parts are adjacent with its bearing 36 need be worked. In thecasting 2, only the surface facing the casting 1 and the inside of theopening 2,5 must be worked. rIfhe illustrations, particularly Fig. 10,indicate that both castings 1 and 2 have smooth surfaces only and noinwardly directed corners which `are difficult to clean. As the othersurfaces ofthe pump are smooth, too, it is suited particularly formedical and hygienic purposes, such as the spraying of ,medicines andthe like for inhaling, it being an easy matter to keep the entire pumpplant in a perfectly sanitary condition.

I claim 1. An electrically operated small-sized piston gas pump unitcomprising, in .combination, a casing and a. suitable cover, both ofwhich `jointly surround a piston pump having centrifugal lubrication,surrounded by the casing, and an oil separator.

2. An electrically operated small-sized piston gas pump unit laccordingto ,claim 1 and a duct connecting the crank case with the atmosphere.

3- A11 electrically @related small-Sized Piston gas pump unit accordingto claim 1, an eleetr@ motor @ed a 'joint casing Surrounding' both the.motor `and the pumpalii 4. An electrically operated small-sized pistongas pump unit according to claim 1 and cast-n cylinder liner made of asubstance differing from that of the metal casing.

5. An electrically operated small-sized piston gas pump unit accordingto claim l and cast-in bushing made of a substance diierng from that ofthe metal of the casing.

6. An electrically operated small-sized piston gas pump unit accordingto claim 1 and two ducts inthe casing and the cover, an eX- tension inthe casing connecting both ducts, and a connecting channel leading fromthe pressure valve to the first one of the two ducts, all ducts beingcast in to the casing.

7. An electrically operated small-sized piston gas pump unit accordingto claim 1 and a nose on the piston in its inner hollow and alubricating aperture in the connecting rod under the nose.

In testimony whereof I have aiixed my signature.

HEINZ SILTEN.

